Connector for stranded cable



Jan. 5, 1954 A. A. BERND-r 2,665,331

CONNECTOR FOR STRANDED CABLE Filed April 4, 1952 2 Sheets-Sheet 1 Jan.5, 1954 A. A. BERNDT CONNECTOR FOR STRANDEO CABLE 2 Sheets-Sheet 2 FiledApril 4, 1952 Patented Jan. 5, 1954 UNITED STATES PATENT OFFICECONNECTOR FOR STRANDED CABLE Arthur A. Berndt, Chicago, Ill., assignorto Electroline Company, Chicago, Ill., a, corporation of IllinoisApplication April 4, 1952, Serial No. 280,512

(Cl. 17d- 94) I cable. In order to successfully grip such a cable foranchoring the same to a support, the two metals must be individuallyclamped so that the strain will be divided between the two metals inproportion to their tensile strength and so that a contact of highconductivity will be made with the outer aluminum strands.

Accordingly an object of the invention is to assemble within a singleconducting metal shell, two or more sets of separate gripping membersdesigned to grip and hold metal wires of different strength,conductivity and hardness, and wherein the intensity of the grip iscontrolled by varying the angle between the gripping member and its cageor shell.

Another object of the invention resides in the provision of a connectorhaving gripping members for engaging the outer wires of the cable andhaving gripping wedges for securely gripping and holding the center wireof the cable, and wherein the gripping elements operate independently ofeach other and stress applied to either set of gripping elements is nottransmitted to the other set.

A further object is to provide a connector for stranded cable having oneor more sets of independent gripping elements and which are capable ofadjustment to any variance in the size of either the steel center strandor in the outer aluminum wires as may occur due to manufacturingtolerances or differences in type of construction for the same sizecable.

A further object is to provide a stranded cable connector of improvedconstruction and operation which will essentially consist of a metalshell having tapered end portions each housing a set of gripping membersfor holding the outer strands of the cable, and wherein said shell will,also house a steel cage in tandem relation with respect to the grippingmembers respectively, which is secured to the shell by peening andcontains a set of gripping wedges `whereby to grip the center steel wireof the cable.

With these and various other objects in view 2 the invention may consistof certain novel features of construction and operation as wil-1 be morefully described and particularly pointed out in the specication,drawings and claims appended hereto.

In the drawings which illustrate embodiments of the invention andwherein like reference characters are used to designate like parts-Figure l is an elevational view of the stranded wire connector of theinvention with parts oi y the shell being broken away to show structuraldetails of the gripping elements;

Figure 2 is an enlarged sectional view of one end of the presentconnector taken longitudinally and illustrating the construction of thegripper elements and their independent coaction;

Figure 3 is an enlarged sectional view of one end of the presentconnector similar to Figure 24 but illustrating the action of thegripping elements when in gripping relation with a strandedA Figure 7 isa transverse sectional view taken on line 'I-'I of Figure 3;

Figure 8 is a detail sectional view illustrating the Icoupling means forthe gripping members; and,

Figure 9 is a perspective view of the retaining cone for the grippingwedges.

The invention is shown as embodied in a connector for stranded wire orcable, having outer wires cf aluminum or similar material of highelectrical conductivity, and having a steel center wire which assumesthe major part of the tension placed on the conductor when in use.

As best shown in Figure l, the connector includes a housing or casing oftubular form, generally designated by the numeral I2, and which may beof any suitable metal, preferably copper or aluminum and having atleastone end thereof tapered to form the tapering end portion I3. In theillustrated embodiment of Figure 1, both ends are reduced in diameter bya. swaging operation, and accordingly, one end is identified byl thenumeral I3 and the other end by the numeral I4. It will be observed thatthe metal at each end opening, namely I5 and I6, is correspond-v This isa desirable the wedges 2G will move rearwardly against the tension ofthe coil spring 4|. Eventually, however, the gripping wedges will expandand assume full contact with the center steel strand, and upon forwardtension being placed on the cable, the wedges will engage the taperingsurfaces 30, causing the wedges to bite into and grip the center steelstrand.

In accordance with the invention, the intensity of the grip effected bythe gripping members and by the gripping wedges respectively, can beadjusted by varying the taper of the surfaces with which the elementscontact. The particular angle of the taper for the gripping members, andlikewise the particular angle of the taper for the gripping wedges, willvary according to the strength, hardness, conductivity, elasticity andductility or" the various metals in the cable in order to produce asuccessful gripping device. The sets of gripping elements are separate,and they operate independently of each other. Any strain applied toeither side is not transmitted to the other. For example, greatergripping and holding eiiort be expended the gripping wedges and theirassociated structure on the center steel strand oi the cable than isexpended by the gripping members, and should this be the case, the sameis not transmitted in any sense to the gripping members, which may beeffective with somewhat less intensity on the outer wires of thestranded cable, The use of independent gripping elements also providesfor their automatic adjustment due to variance in the size or either thesteel or aluminum strand, as occurs due to manufacturing tolerances, ordifference in type of construction for the same size of cable.

The invention is not to be limited to or by details of construction ofthe particular embodiment selected for illustration in the drawings, asvarious forms of the device will of course be apparent to those skilledin the art without departing from the spirit ci the invention or thescope of the claims.

What is claimed is:

l. A connector for stranded wire conductors comprising a tubular casinghaving a tapering end portion, gripping members arranged within saidtapering end portion and adapted to receive and grip the outer wires ofa conductor inserted within the tapering end portion, means yieldinglyretaining the gripping members in operative connected relation so thatthey coact as a unit in gripping the conductor, other gripping elementslocated rearwardly in tandem relation with respect to the grippingmembers and operative to grip and hold the center wire of saidconductor, said other gripping elements including a cylindrical cagelocated within the casing and secured thereto, said cage having taperingsurfaces interiorly thereof, a plurality of gripping wedges locatedwithin the cage in contact with the interior tapering surfaces thereof,a retainer for the gripping wedges, and resilient means for the grippingmembers and wedges respectivly, for urging the parts in a forwarddirection to maintain them in contact with their tapering surfaces.

2. In a connector for stranded cable having outer wires of aluminum anda center steel wire, the combination including a tubular casing having atapering end portion, `a set of gripping members within said taperingend portion and adapted to receive and grip the outer wires of astranded cable inserted within the tapering end portion, a ring memberat the rear of said gripping members for retaining the members inoperative connected relation so that they coact as a unit in grippingthe cable, a cylindrical cage having tapering interior surfaces locatedrearwardly in spaced relation to the gripping members and being fixedlysecured to the casing, a set or gripping wedges within the cylindricalcage in contact with the tapering interior surfaces thereof and adaptedto grip and hold the center wire of said cable, a retainer for saidgripping Wedges, and resilient means for the gripping members and wedgesrespectively, for urging the parts in a forward direction to maintainthem in contact with their tapering surfaces.

3. In a connector for stranded cable having outer wires of aluminum anda center steel wire, the combination including a tubular casing having atapered end portion, a set oi' gripping members within said tapered endportion and adapted to receive and grip the outer wires of a strandedcable inserted within the tapering end portion, a ring member at therear of said gripping members having articulated relation with eachmember for operatively connecting the members so that they coact as aunit in gripping the cable, a cylindrical cage having tapering interiorsurfaces located rearwardly in spaced relation to the gripping membersand being fixedly secured to the casing, a set oi gripping' Wedgeswithin the cylindrical cage in contact with the tapering interiorsurfaces thereof and adapted to grip and hold the center wire of saidcable, a retainer having slots for receiving the gripping wedges, andresilient means for the gripping members located between the members andthe cage for urging the members in a forward direction to maintain themin contact with their tapered end portion.

4. A connector for stranded cable as defined by claim 3, additionallyincluding other resilient means located within the cage in rear of theretainer and operative to yieldingly urge the retainer in a forwarddirection to maintain the gripping wedges in contact with their taperingsurfaces.

5. In a connector for stranded cable and the like, the combinationincluding a tubular casing having a tapered end portion, a set ofgripping members within said tapered end portion and adapted to receiveand grip the outer wires of a stranded cable inserted within the taperedend portion, said gripping members as a set being cone-shaped and havingsurfaces conforming to and in contact with the tapering walls of saidportion, a rear extension provided by each gripping member, a ringmember at the rear of said gripping members, said extensions havingtelescoping relation with the ring member, means projecting radiallyfrom the ring member and having articulated relation with the extensionsrespectively, so that they move and coact as a unit in gripping thecable, and a coil spring for the gripping members for urging the membersin a forward direction to maintain them in contact with the walls ofsaid tapered end portion.

ARTHUR. A. BERNDT.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,158,892 Becker et al May 14, 1939 2,166,457 Berndt July 18,1939 2,209,620 Berndt et al July 30, 1940 2,222,494 Barlow Nov. 19, 1940

